Tissue homogenization buffer

10 mM HEPES-KOH (pH 7.6)

25 mM KCl

0.15 mM spermine

0.5 mM spermidine

2 M sucrose

10% (v/v) glycerol

1 mM EDTA (pH 8.0)

The buffer should be ice cold at the time of use. Add protease inhibitors such as 0.5 mM phenylmethylsulfonyl fluoride (PMSF), 1 μg/ml leupeptin, 1 μg/ml pepstatin, or others as needed, just before Step 1.